Green Healthcare, Part 2: Clean Water - Good for Nature, Good for Permits

Every building project is either positively or negatively effecting the environment - that includes hospitals. Green hospitals are complex buildings, and take effort to make green. The first step to achieve a healthy hospital (no matter the scope or location) is to focus outdoors with the site planning. Site design plays a pivotal role in providing savings for green design - savings that will be vital in later stages of the project. Moreover, landscape architecture is the best way to prevent unnecessary stormwater problems as well as help with securing municipal approval and community support.

Graphic Credit: inFORM StudioCommunity Support is a Good ThingNot all projects need overwhelming community support, but community hospitals do. Site plans are the first piece of a hospital design that is reviewed by municipal authorities, and the first to be scrutinized by the public. With many towns and cities facing chronic flooding, degraded water quality and increasing costs to tax payers for water management, a project will not give the go ahead, in the form of site plan approval or building permits without local decision makers seeing evidence that stormwater is being dealt with appropriately. The current method to do this is by simply designing large retention and detention ponds to hold water for set amount of time defined for local, state or federal guidelines. These large pools are expensive, increase liability and add no aesthetic value to a project. They can be difficult to locate when a site is small. In the end, they are eye sores and not very imaginative.

Until the late 80s, the standard stormwater management practice was to collect storm water from impervious surfaces, pipe it underground to the edge of the property, discharged it into the municipal storm water system which then simply dumped it into the nearest natural body of water. The practice had numerous deleterious effects including the increase of pollutants, the depletion of aquifers, and reoccurring flooding. Although the introduction of Best Management Practices improved water quality issues, much of the same collect-it-and-pipe-it mentality persists.

Closed-Loop Water SystemsWhen the design team for UPMC-East began, we considered water as a closed loop system meaning that the majority of the water that falls via rain is used on the site. If all projects approach stormwater this way we could reverse the paradigm of site design to benefit the planet, society, and economy.

Erroneously, people tend to compare sustainable products to non-sustainable products (the apple-to-apples mentality). This often reveals that the better-for-the-environment option costs more than the bad-for-the-environment selection. But comparing product to product is not the best way to find savings with green building. For example, designing a high performance building envelope takes less materials overall and reduces tonnage of HVAC equipment. This equals big cost reductions, however if you compare better quality insulation to standard insulation - it first seems that the green direction is going to cost more. Site work works the same way. Green options like bioswales, stormwater mitigation and native flora species can, at first, seem to cost more, but as the UPMC-East project proved, these methods reduced the cost of retention ponds while adding value to landscaping. The bioswales we designed for UPMC-East are not only a sustainable rainwater solution; they become amenities for the hospital as respite for employees and patients.

The UPMC-East site in Monroeville, Pennsylvania is an existing sixteen acre greyfield site that contained a nine story hotel with a colorful history. It also exemplifies the old paradigm. The naturally sloped site was artificially flattened with seventy feet of uncompacted fill that was asphalted and one hundred percent impervious. The asphalted surface shed rainwater run-off into the adjacent road creating unsafe conditions during wet weather. To the southern edge of the site a man-made hundred foot embankment led to a stream called Dirty Camp Run. The stream was fed by a seventy-two inch corrugated metal pipe running underneath the site carrying stormwater from the adjacent 450 acres and dispersing it into the creek. Like a scene lifted out of the 2008 animated film Wall-E, the site represented everything that is wrong site design and landscaping.

Thinking Big Helps Designing BetterTo reverse the found condition, site analysis began by erasing the site boundaries and looking for natural and urban connections beyond the sixteen acres. Research revealed that Dirty Camp Run ties into Turtle Creek which ties into the Monongahela which ties into the Ohio which eventually ties into the Mississippi River. So, in essence, the sixteen acre site contains far reaching implications being tied to the one of the largest watersheds in the world.

Downstream were well-documented flooding that caused loss of life and significant property damage because of bad stormwater management. The flooding was the subject of legal woes and concern to residents. The local governments responded by requiring developers reduce post-development run-off by twenty percent. This usually means retention and detention ponds.

A three-pronged approach was established for a more sustainable response to the site and to the region. First, rather than burying the stormwater management system in expensive engineered systems, the water was exposed allowing it to be naturally cleaned, absorded and evaporated. Rain gardens were incorporated throughout the site to collect and hold rainfall to recharge the water table. Bioswales are used to naturally move the water to a series of pools where the sediment and contaminants can settle before moving it to natural streams.

Second, the types of ground covering were chosen by its curve number. Curve numbers, or CN, are assigned to different conditions to characterize runoff properties. High CN values like asphalt indicate more run-off while lower values like deep soils or grass indicate increased absorption. We worked to maximize areas of imperviousness and absorption to active the landscaping as catchments areas. This also allowed us to choose more native plants which require less artificial irrigation and less maintenance. In the end, we were able to completely eliminate any additional irrigation for the site. The result is a more natural looking design.

The shift may upset fans of manicured lawns, but the lack of ongoing maintenance, irrigation, and fertilizer cuts operation costs by more than 50 percent. Thirdly, the unsuitable fill was removed to restore the topography closer to its natural condition and habitat. The design uses the restored topography to guide the water to the edge of the site, descending in a series of bioswales before ending in a retention pond. The retention pond releases the water into creek in a controlled manner. These three steps reduced the sizes of the retention ponds considerably which knocked off cost for excavating and hauling dirt from the site.

Green Design doesn't have to Cost MoreWithout spending a penny more in overall site development costs, the new community hospital's post-development run-off was reduced by more than 40 percent - twice that of the requirements by the local authority. Moreover, all of the water coming from the site will be virtually pollutant-free when it goes into Dirty Camp Run. The integrated landscape/stormwater solution return of investment was that the municipality approved the site plan faster - saving money by eliminating repeat submissions, additional engineering services and costly delays to the project's schedule. Local residents were, at first, against the development of UPMC-East but supported a rival hospital. When our design was presented and the mayor explained that the design doubled reductions of stormwater, citizens began to support the development quickly understanding the larger implications.